Muslinoma and muslin-induced foreign body inflammatory reactions after surgical clipping and wrapping for intracranial aneurysms: imaging findings and clinical features

Possible Delayed Foreign Body Reactions against Titanium Clips and Coating Materials after Unruptured Cerebral Aneurysm Surgery

Delayed foreign body reactions to either or both clipping and coating materials have been reported in several small series; however, studies in the titanium clip era are scarce. This study aims to survey the contemporary status of such reactions to titanium clips and coating materials. Among patients who received a total of 2327 unruptured cerebral aneurysmal surgeries, 12 developed delayed intraparenchymal reactions during outpatient magnetic resonance imaging (MRI) follow-up. A retrospective investigation was conducted. The patients' average age was 58.6 (45-73) years, and 11 were women. The aneurysms were located in the middle cerebral artery (n = 7), internal carotid artery (n = 4), or anterior communicating artery (AComA, n = 1). In 10 patients, additional coating with tiny cotton fragments was applied to the residual neck after clipping with titanium clips; however, only the clipping with titanium clips was performed in the remaining two. The median time from surgery to diagnosis was 4.5 (0.3-60) months. Seven (58.3%) patients were asymptomatic, and three developed neurological deficits. MRI findings were characterized by a solid- or rim-enhancing lobulated mass adjacent to the clip with surrounding parenchymal edema. In 11 patients, the lesions reduced in size or disappeared; however, in one patient, an AComA aneurysm was exacerbated, necessitating its removal along with optic nerve decompression. In conclusion, cotton material is a strongly suspected cause of delayed foreign body reactions, and although extremely rare, titanium clips alone may also induce such a reaction. The prognosis is relatively good with steroid therapy; however, caution is required when the aneurysm is close to the optic nerve, as in AComA aneurysms.

The leptomeninges as a critical organ for normal CNS development and function: First patient and public involved systematic review of arachnoiditis (chronic meningitis)

BACKGROUND & IMPORTANCE

This patient and public-involved systematic review originally focused on arachnoiditis, a supposedly rare "iatrogenic chronic meningitis" causing permanent neurologic damage and intractable pain. We sought to prove disease existence, causation, symptoms, and inform future directions. After 63 terms for the same pathology were found, the study was renamed Diseases of the Leptomeninges (DLMs). We present results that nullify traditional clinical thinking about DLMs, answer study questions, and create a unified path forward.

METHODS

The prospective PRISMA protocol is published at Arcsology.org. We used four platforms, 10 sources, extraction software, and critical review with ≥2 researchers at each phase. All human sources to 12/6/2020 were eligible for qualitative synthesis utilizing R. Weekly updates since cutoff strengthen conclusions.

RESULTS

Included were 887/14286 sources containing 12721 DLMs patients. Pathology involves the subarachnoid space (SAS) and pia. DLMs occurred in all countries as a contributor to the top 10 causes of disability-adjusted life years lost, with communicable diseases (CDs) predominating. In the USA, the ratio of CDs to iatrogenic causes is 2.4:1, contradicting arachnoiditis literature. Spinal fusion surgery comprised 54.7% of the iatrogenic category, with rhBMP-2 resulting in 2.4x more DLMs than no use (p<0.0001). Spinal injections and neuraxial anesthesia procedures cause 1.1%, and 0.2% permanent DLMs, respectively. Syringomyelia, hydrocephalus, and arachnoid cysts are complications caused by blocked CSF flow. CNS neuron death occurs due to insufficient arterial supply from compromised vasculature and nerves traversing the SAS. Contrast MRI is currently the diagnostic test of choice. Lack of radiologist recognition is problematic.

DISCUSSION & CONCLUSION

DLMs are common. The LM clinically functions as an organ with critical CNS-sustaining roles involving the SAS-pia structure, enclosed cells, lymphatics, and biologic pathways. Cases involve all specialties. Causes are numerous, symptoms predictable, and outcomes dependent on time to treatment and extent of residual SAS damage. An international disease classification and possible treatment trials are proposed.

Occam or Hickham? The diagnostic dilemma of an inflammatory brain lesion in the setting of pulmonary aspergillosis and previous neurosurgery

INTRODUCTION

Occam's Razor is a precept which invites one to consider the simplest and most unifying diagnosis as correct. In the modern era, clinical diagnosis remains critical in selecting appropriate therapies yet grows ever more complex with increased information from diagnostic technologies, but not always with sufficient granularity to answer the clinical question with certainty. We present an example of this dilemma in a patient with complex partial seizures on a background of pulmonary aspergillosis and historic clipping of a middle cerebral artery (MCA) aneurysm.

CASE DESCRIPTION

A 69-year-old female presented with progressive headaches, temporal lobe seizures, poor short-term memory and weight loss. She had suffered a subarachnoid haemorrhage 22 years earlier requiring surgical repair of a right MCA aneurysm. She was treated for breast cancer in 2006 followed by pulmonary aspergilloma in 2014 for which systemic antifungals were discontinued due to toxicity. Imaging revealed a right temporal inflammatory lesion adjacent to the aneurysm clip. Gastrointestinal toxicity and haemoptysis complicated the clinical and radiological response to systemic steroids. Cerebral aspergillosis was considered given her medical history despite an equivocal fungal screen, but intolerable side effects negated the continued use of systemic antifungals. Surgical exploration to establish a definitive diagnosis and potentially treat the underlying cause was recommended despite the high surgical risk involved and subsequently revealed a foreign body type granuloma, and excluded aspergillosis. Tuberculosis and other granulomatous disease processes were excluded.

CONCLUSION

This case illustrates the importance of pathological diagnosis to guide therapy and reminds us that the occasional patient will encounter multiple, rare and unrelated diseases during their lifetime. A high index of suspicion is necessary in patients who have undergone surgical aneurysm repair involving muslin as it may be subject to secondary infection and or granuloma formation many years later.

MRI findings for diagnosis of postoperative foreign body granulomas versus recurrent tumours in patients of brain tumour surgery

AIM

To evaluate the postoperative magnetic resonance imaging (MRI) findings of intracranial foreign body granulomas (FBGs) and true recurrent tumours (RTs) and thus lead to a basis for management decision-making.

MATERIALS AND METHODS

Twenty-two patients with previous brain tumour surgery were diagnosed clinically with RT and underwent surgery. Re-operative pathology revealed FBG in eight patients and RT in 14 patients. MRI findings before the initial operation were compared to those before the re-operation.

RESULTS

Features of FBGs versus RTs on MRI were as follows: (1) mean lesion size: 1.3 ± 0.7 (0.5-2.6) versus 3.2 ± 1.7 (1.1-6.3) cm (p=0.001, odds ratio [OR] = 4.18); (2) hypointensity on T2-weighted imaging (WI): 6/8 (75%) versus 0/14 (0%; p<0.001, OR=75.4); (3) non-restricted diffusion on diffusion-WI (DWI): 6/8 (75%) versus 2/14 (14.3%; p=0.008, OR=18); and (4) "ring and bubble" appearance on contrast-enhanced T1WI: 7/8 (87.5%) versus 2/14 (14.3%; p=0.001, OR=42). In comparison with their original tumours, the FBGs in the FBG group showed significantly lower T2 signal intensity, lower signal on DWI, and more cases of non-restricted diffusion on DWI (p=0.04, 0.04, 0.04, respectively).

CONCLUSION

On brain MRI, FBGs can be differentiated from RTs by their relatively smaller size, hypointensity on T2WI, lack of restricted diffusion on DWI, and "ring and bubble" appearance on contrast-enhanced T1WI. Comparing the MRI findings of the focal lesion in the tumour bed with those of the original tumour is suggested to enhance diagnostic confidence.

Case Report: Late Sequela of a Muslinoma Involving the Optic Chiasm

An 84-year-old woman presented with 3 months of vertical binocular diplopia and difficulty reading at near. She had a history of bilateral ophthalmic artery aneurysm repair involving use of muslin in the 1990s. The patient then developed bitemporal hemianopsia secondary to muslin-induced inflammation ("muslinoma") extending to the optic chiasm, which required surgical decompression. She had a persistent bitemporal hemianopsia but was stable for two decades after surgery. In 2017, the patient re-presented with double vision. Exam showed a non-paretic diplopia due to a small angle comitant right hypertropia attributed to the retinal hemi-field slide. Repeat imaging showed no new aneurysm or recurrent muslinoma. This case had originally been reported two decades ago and represents the longest duration of recurrent symptoms from muslin-related optochiasmatic arachnoiditis in the English language ophthalmic literature. Clinicians should be aware of the potential of delayed and recurrent symptoms or signs years or even decades after muslin wrapping of aneurysms.

Surgical treatment of a gauzoma with associated obliterative arteriopathy and review of the literature

We report a case of a 50-year-old woman whose 0.5 mm middle cerebral artery (MCA) aneurysm was treated with gauze wrapping at an outside facility. She returned 9 months later with seizures and an inflammatory process in the region of the prior aneurysm. Surgical re-exploration at that time was aborted. Two years later, she presented with a gauzoma associated with local inflammatory response and severe narrowing of the MCA. A common carotid artery to MCA bypass was performed, followed by surgical removal of the gauze and inflammatory material. Over a 3-month period, she recovered with significant improvement in her preoperative neurological deficits.

Techniques and Outcomes of Gore-Tex Clip-Wrapping of Ruptured and Unruptured Cerebral Aneurysms

OBJECTIVE

Some aneurysms without a definable neck and associated parent vessel pathology are particularly difficult to treat and may require clipping with circumferential wrapping. We report the largest available contemporary series examining the techniques of Gore-Tex clip-wrapping of ruptured and unruptured intracranial aneurysms and patient outcomes.

METHODS

The presentation, location, and shape of the aneurysm; wrapping technique; outcome at discharge and last follow-up; and any change in the aneurysm at last angiographic follow-up were reviewed retrospectively in 30 patients with Gore-Tex clip-wrapped aneurysms.

RESULTS

Gore-Tex clip-wrapping was used in 8 patients with ruptured aneurysms and 22 patients with unruptured aneurysms. Aneurysms included 23 fusiform, 3 blister, and 4 otherwise complex, multilobed, or giant aneurysms. Of the 30 aneurysms, 63% were in the anterior circulation. The overall mean patient age was 52.5 years (range, 17-80 years). Postoperatively, there were no deaths or worsening of neurologic status and no parent vessel stenoses or strokes. The mean Glasgow Outcome Scale score at last follow-up was 4.7. The mean follow-up time was 42.3 months (median, 37.0 months; range, 3-96 months). There were 105.8 patient follow-up years. Aneurysms recurred in 2 patients with Gore-Tex clip-wrapping. No patients developed rehemorrhage. Overall risk of recurrence was 1.9% annually.

CONCLUSIONS

Gore-Tex has excellent material properties for circumferential wrapping of aneurysms and parent arteries. It is inert and does not cause a tissue reaction or granuloma formation. Gore-Tex clip-wrapping can be used safely for microsurgical management of ruptured and unruptured cerebral aneurysms with acceptable recurrence and rehemorrhage rates.

Techniques and long-term outcomes of cotton-clipping and cotton-augmentation strategies for management of cerebral aneurysms

OBJECTIVE To address the challenges of microsurgically treating broad-based, frail, and otherwise complex aneurysms that are not amenable to direct clipping, alternative techniques have been developed. One such technique is to use cotton to augment clipping ("cotton-clipping" technique), which is also used to manage intraoperative aneurysm neck rupture, and another is to reinforce unclippable segments or remnants of aneurysm necks with cotton ("cotton-augmentation" technique). This study reviews the natural history of patients with aneurysms treated with cotton-clipping and cotton-augmentation techniques. METHODS The authors queried a database consisting of all patients with aneurysms treated at Barrow Neurological Institute in Phoenix, Arizona, between January 1, 2004, and December 31, 2014, to identify cases in which cotton-clipping or cotton-augmentation strategies had been used. Management was categorized as the cotton-clipping technique if cotton was used within the blades of the aneurysm clip and as the cotton-clipping technique if cotton was used to reinforce aneurysms or portions of the aneurysm that were unclippable due to the presence of perforators, atherosclerosis, or residual aneurysms. Data were reviewed to assess patient outcomes and annual rates of aneurysm recurrence or hemorrhage after the initial procedures were performed. RESULTS The authors identified 60 aneurysms treated with these techniques in 57 patients (18 patients with ruptured aneurysms and 39 patients with unruptured aneurysms) whose mean age was 53.1 years (median 55 years; range 24-72 years). Twenty-three aneurysms (11 cases of subarachnoid hemorrhage) were treated using cotton-clipping and 37 with cotton-augmentation techniques (7 cases of subarachnoid hemorrhage). In total, 18 patients presented with subarachnoid hemorrhage. The mean Glasgow Outcome Scale (GOS) score at the time of discharge was 4.4. At a mean follow-up of 60.9 ± 35.6 months (median 70 months; range 10-126 months), the mean GOS score at last follow-up was 4.8. The total number of patient follow-up years was 289.4. During the follow-up period, none of the cotton-clipped aneurysms increased in size, changed in configuration, or rebled. None of the patients experienced early rebleeding. The annual hemorrhage rate for aneurysms treated with cotton-augmentation was 0.52% and the recurrence rate was 1.03% per year. For all patients in the study, the overall risk of hemorrhage was 0.35% per year and the annual recurrence rate was 0.69%. CONCLUSIONS Cotton-clipping is an effective and durable treatment strategy for intraoperative aneurysm rupture and for management of broad-based aneurysms. Cotton-augmentation can be safely used to manage unclippable or partially clipped intracranial aneurysms and affords protection from early aneurysm re-rupture and a relatively low rate of late rehemorrhage.

Gossypiboma revisited: A never ending issue

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Retained foreign objects (RFO), is one of the most dreadful complications of surgery.

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Despite a seemingly correct count, laparotomy pads were missed at the end of surgery in three patients.

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Human errors continue to occur and RFO continues to plague the surgical practice.

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To avoid human error, one of several recent technologies designed to check for items left behind, should be employed.

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In our report, we give an important tip on how to extract the retained surgical sponge without causing much damage.

Introduction

Leaving a surgical item inside the patient at the end of surgery, is one of the most dreadful complications. The item is frequently a surgical sponge and the resultant morbidity is usually severe. Additionally, the event poses considerable psychic strain to the operating team, notably the surgeon.

Presentation of cases

Here we describe the clinical course of three patients in whom a surgical sponge was missed, despite a seemingly correct count at the end of difficult caesarean sections. In two patients, who presented shortly after surgery, the pad was extracted with no bowel resection. In the third patient, who presented several years after surgery, colectomy was performed.

Discussion

Gossypiboma is under reported and the true incidence is largely unknown. Depending on the body reaction and the characters of the retained sponge, the patient may present within months to years after surgery. Risk factors for retained foreign objects include emergency surgery, an unplanned change in the surgical procedure, higher body mass index, multiple surgical teams, greater number of major procedures done at the same time and incorrect count recording. The surgical procedure needed to extract the retained sponge may be a simple one, as in the first case, or it may be more complex, as seen in the other two cases. Although holding the correct count at the end of surgery is the gold standard safeguard against this mishap, human errors continue to occur, as happened in our patients. For that reason, the correct count should be supplemented by employing one of the several new technologies currently available.

Conclusion

Gossypiboma continues to occur, despite precautionary measures. As its consequences might cost the patient his life and the surgeon his professional reputation, extra preventive measures should be sought and implemented. New advances in technology should be incorporated in the theatre protocol as additional safeguard against human error. When encountered, a direct incision over the encapsulated swelling, in contrast to a formal laparotomy incision, might simplify the surgical procedure.

Enhancing brain lesions after endovascular treatment of aneurysms

Complications of endovascular therapy of aneurysms mainly include aneurysm rupture and thromboembolic events. The widespread use of MR imaging for follow-up of these patients revealed various nonvascular complications such as aseptic meningitis, hydrocephalus, and perianeurysmal brain edema. We present 7 patients from 5 different institutions that developed MR imaging-enhancing brain lesions after endovascular therapy of aneurysms, detected after a median time of 63 days. The number of lesions ranged from 4-46 (median of 10.5), sized 2-20 mm, and were mostly in the same vascular territory used for access. Three patients presented with symptoms attributable to these lesions. After a median follow-up of 21.5 months, the number of lesions increased in 2, was stable in 1, decreased in 3, and disappeared in 1. The imaging and clinical characteristics suggested a foreign body reaction. We could find no correlation to a specific device, but a possible source may be the generic hydrophilic coating.

Long-term MRI findings of muslin-induced foreign body granulomas after aneurysm wrapping. A report of two cases and literature review

Muslin-induced foreign body granulomas are rare delayed complications after wrapping of intracranial aneurysms. Few small case series have been reported, with a paucity of documented MRI findings. In addition, there are no reports on long-term radiological appearances or temporal evolution of conservatively managed patients. We thus report on the long-term radiological and clinical follow-up of two patients with asymptomatic muslin-induced foreign body granulomas after wrapping of recurrent middle cerebral arterial aneurysms. Both patients were successfully managed conservatively and remain asymptomatic three and six years after diagnosis of their granulomas. A literature review confirms that MRI features of muslin-induced foreign body granuloma are typical. Features include focal areas of elevated T2 signal with increased diffusion-weighted signal and thin rim enhancement. To the best of our knowledge, this is the first report to confirm that there is a corresponding reduction in apparent diffusion coefficient, as typical in an intracranial abscess. Thus a history of aneurysm wrapping is critical for diagnosis. Accurate clinical recognition of this exuberant inflammatory response will avoid misdiagnosis as pyogenic abscess or tumor and prevent unnecessary or invasive treatment.

Endovascular treatment of recurrent intracranial aneurysms following previous microsurgical clipping with the Pipeline Embolization Device

The treatment of intracranial aneurysms with microsurgical clipping is associated with a very low rate of recurrence. However, in cases of aneurysm recurrence after previous clipping, microsurgical dissection due to adhesions and fibrosis may be challenging, and it may be difficult to safely occlude the recurrent lesion without the risk of significant morbidity. Flow-diverting stents have drastically changed the landscape of endovascular neurosurgery. We present two patients with large, recurrent supraclinoid internal carotid artery (ICA) aneurysms which were previously clipped 17 and 23 years ago at outside institutions. Both recurrent lesions were treated with the Pipeline Embolization Device (PED; ev3 Endovascular, Irvine, CA, USA) without radiographic or clinical complications. In the first patient, the 15 mm aneurysm significantly decreased in size at 6 month angiographic follow-up. The 21 mm aneurysm in the second patient was completely occluded 7 months following PED treatment. The moderate degree of in-stent stenosis present on initial follow-up imaging resolved on angiography 11 months post-treatment. The management of recurrent aneurysms after clipping is sparsely reported in the literature due to its infrequent occurrence. In carefully selected cases, flow-diverting stents may be used for complex aneurysms of the distal ICA, even for those which have recurred following microsurgical clipping.

Cerebrovascular complications and granuloma formation after wrapping or coating of intracranial aneurysms with cotton gauze and human fibrin adhesives: results from a single-center patient series over a 5-year period

Object

Reinforcement of intracranial aneurysms (IAs) by wrapping or coating is a well-established therapeutic approach to those IAs not amenable to any other definitive treatment, but has been associated with complications such as parent artery narrowing, granuloma formation, and ischemic stroke. The goal of this study was to systematically investigate cerebrovascular complications following this procedure.

Methods

The authors' hospital database was searched for all patients who underwent wrapping or coating of IAs with cotton gauze and human fibrin adhesives between October 2006 and October 2011. The follow-up records of these patients were extracted, including regular clinical visits and vascular imaging.

Results

Five hundred sixty-seven patients were treated for IAs over the 5-year period: 303 patients underwent endovascular strategies and 264 underwent craniotomies. Wrapping or coating of IAs was performed in 20 patients (3.5%). Parent artery narrowing occurred in 5 (25%) of the 20 patients and was associated with major ischemic strokes in 4 patients and severe headache in another. Ischemic strokes were associated with parent artery narrowing, which occurred early postoperatively in 2 patients or was a consequence of granuloma formation in 2 patients 1 and 2 months after the procedure, respectively.

Conclusions

These data should add to the awareness of significant cerebrovascular complications following wrapping or coating of IAs with cotton gauze and human fibrin adhesives and indicate that major ischemic strokes need to be included in the risk/benefit considerations during decision making for such treatment strategies. Patients who receive IA wrapping should be monitored and followed up closely for arterial narrowing and granuloma formation.

Muslin-induced intracranial vasculopathic stenosis: a report of two cases

Muslin wrapping is a commonly utilized alternative technique in the treatment of aneurysms that are not amenable to direct clipping. In this case report, we describe two patients from different institutions who both required aneurysm wrapping with gauze/muslin for aneurysm reinforcement. Both patients developed an inflammatory foreign body response to muslin visible on MRI that resulted in a vasculitic stenosis. The onset of TIAs was at 6 months and 1 month postoperatively, respectively. The stenoses rapidly progressed to near occlusion despite antiplatelet therapy, and in one case, an aggressive corticosteroid regimen. One patient eventually developed leptomeningeal collateral flow that allowed tolerance of the stenosis, while the other patient required microsurgical bypass. These cases reports are the first to our knowledge that describe the adverse effects of muslin wrapping without adhesive reinforcement, as well as one of few reports to include follow-up angiographic imaging.